The "Woad Root" you refer to is typically known as Dyer's Woad - You'll find it as a weed in many locales.

Note this is a cousin to the above mentioned TCM medicinal: Radix Isatidis.

Not sure about medicinal use, but its the same chemical for the Blue Dye in Woad that is also present in real Indigo - Just that Woad is much less concentrated.

Herr Schlüggell -- Establish a Garden; Cultivate Community. "To see things in the seed, that is genius. He who obtains has little. He who scatters has much. The way to do is to be." -Lao TzuBruno Manser, Ned Lud, August Sabbe, Richard St. Barbe-Baker, Eddie Koiki Mabo, Masanobu Fukuoka

I just emailed Dr. D, and suggested that he revise the listing for woad root so that, at the very least, it's also listed by its alias, "indigo root" or whatever, and that the listing also specifies that it can be found in Rekon Pro.

The plant you mention is not the True Indigo {Indigofera sp.}, but a cousin...

There is some mention in the Science database for Baptisia sp.

Herr Schlüggell -- Establish a Garden; Cultivate Community. "To see things in the seed, that is genius. He who obtains has little. He who scatters has much. The way to do is to be." -Lao TzuBruno Manser, Ned Lud, August Sabbe, Richard St. Barbe-Baker, Eddie Koiki Mabo, Masanobu Fukuoka